This trial evaluates the ability of a novel vaccine to stimulate anti-tumor immune responses and proved therapeutic benefit in an adjuvant setting. The vaccine consists of autologous peripheral blood dendritic cells (professional antigen presenting cells) collected by apheresis, pulsed with individualized tumor idiotype protein, and reinfused into the patient. Twenty-seven patients with low grade non-Hodgkin's lymphoma have completed vaccination with four courses of idiotype-pulsed autologous dendritic cells. The dendritic cell infusions have been very well tolerated with rare infusion reactions which are tolerable and easily controlled. There is no evidence of acute or chronic toxicity. Sixteen of these 27 patients have developed measureable anti-idiotype T-cell proliferative responses, suggesting the possibility of an anti-tumor effect. Still no patients have produced measureable humoral anti-idiotype responses, unlike patients treated with our standard vaccine. This may be a true characteristic of the dendritic cell approach. Several patients did experience tumor regressions during and after dendritic cell vaccination. Of the ten initial patients we treated with measurable, chemotherapy-resistant tumors, three objective responses were observed, including two complete responses. The remaining 17 patients have been vaccinated in first remission following chemotherapy. Two of these patients, and eight of the latter patients have developed progressive disease within several years of vaccination. These are patients with a poorer prognosis defined by suboptimal response to initial chemotherapy. As the trial continues to accrue, we will have a larger population whose clinical responses can be compared to the expected clinical course for comparable patients.